diff --git a/Project.toml b/Project.toml
index 96aaa00..d185f63 100644
--- a/Project.toml
+++ b/Project.toml
@@ -1,6 +1,6 @@
 name = "FastTransforms"
 uuid = "057dd010-8810-581a-b7be-e3fc3b93f78c"
-version = "0.17.4"
+version = "0.17.5"
 
 
 [deps]
diff --git a/src/libfasttransforms.jl b/src/libfasttransforms.jl
index fc3fdef..c42dabc 100644
--- a/src/libfasttransforms.jl
+++ b/src/libfasttransforms.jl
@@ -1294,4 +1294,5 @@ function modified_jacobi_matrix(R, XP)
     return XQ
 end
 
-inv(P::FTPlan{T,2,DISKANALYSIS}) where T = plan_disk_synthesis(T, P.n, P.m)
\ No newline at end of file
+inv(P::FTPlan{T,2,DISKANALYSIS}) where T = plan_disk_synthesis(T, P.n, P.m)
+inv(P::FTPlan{T,2,DISKSYNTHESIS}) where T = plan_disk_analysis(T, P.n, P.m)
\ No newline at end of file
diff --git a/test/libfasttransformstests.jl b/test/libfasttransformstests.jl
index 7828ab0..3fa5dca 100644
--- a/test/libfasttransformstests.jl
+++ b/test/libfasttransformstests.jl
@@ -174,11 +174,18 @@ FastTransforms.ft_set_num_threads(ceil(Int, Base.Sys.CPU_THREADS/2))
     @test inv(pa) isa typeof(ps)
     @test inv(pa)*(p*A) ≈ ps*(p*A)
     @test p\(pa*(inv(pa)*(p*A))) ≈ A
+    @test inv(ps) isa typeof(pa)
+    @test inv(ps)*(ps*(p*A)) ≈ pa*(ps*(p*A)) ≈ p*A
+    @test p\(inv(ps)*(ps*(p*A))) ≈ A
+    @test inv(inv(ps)) isa typeof(ps)
+    @test inv(inv(pa)) isa typeof(pa)
     A = diskones(Float64, n, 4n-3) + im*diskones(Float64, n, 4n-3)
     p = plan_disk2cxf(A, α, β)
     ps = plan_disk_synthesis(A)
     pa = plan_disk_analysis(A)
     test_nd_plans(p, ps, pa, A)
+    @test inv(pa)*(p*A) ≈ ps*(p*A)
+    @test inv(ps)*(ps*(p*A)) ≈ p*A
 
     A = diskones(Float64, n, 4n-3)
     p = plan_ann2cxf(A, α, β, 0, ρ)